The raven paradox, also known as Hempel’s paradox, Hempel’s ravens or, rarely, the paradox of indoor ornithology, is a paradox arising from the question of what constitutes evidence for the truth of a statement.

  • BlackRoseAmongThorns@slrpnk.net
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    1 month ago

    You’re correct, it says so in the article further down, It’s not a paradox in the “formal” sense, it’s only a paradox in the sense of what intuitively would be considered evidence, but in actuality isn’t, I’ll try to give an easier example to demonstrate use of actual basic logic.

    Claim: “all natural* numbers are even”.

    • Natural: whole number which is zero or greater. (Zero not always included, blame mathematicians)
    1. Notice that pointing at a natural number which doesn’t contradict the claim, isn’t evidence, and that exists infinitely many natural numbers who don’t contradict the claim (2, 4, …), yet 1 does, and is considered evidence to the contrary.

    2. Notice that pointing at a non-natural number, which doesn’t satisfy the claim, also isn’t evidence, also in this case there are infinitely many such numbers (-1, -3, ½,…).

    Also as a demonstration, let’s invert the claim formally, we swap “all” with “exists”, and invert predicates: “exists a natural number which isn’t even”, this inverse is useful because it can point to how to disprove the original claim, because there exists such a number (1), i can say that i proved the inverse of the original claim, this is equivalent to disproving it.

    Tldr: the paradox is a short exercise in how formal logic differs from naive intuition, there isn’t really a paradox.